1. Field of the Invention
The present invention relates to coupling elements such as microwave waveguide coupling elements, in particular to flanges and body heads, inserts and the like, for joint formers for coupling duct elements, at least one of which duct elements has a non circular section, including a core provided with holes for fastening members and an opening, generally located at the center, provided with a recess hollowed out in one own face of more immediate realization.
2. Background Information
With reference to the specific case of waveguides, it is known that most passive components, e.g., filters, circulators, couplers, isolators, terminations, etc., and active components, e.g., an oscillator with a cavity resonator at the output, or semiactive components, have outputs that have to enter waveguide sections. Normally when there is no problem as to space, coupling does not give rise to unsurmountable problems. However, in most of the actual appliances there is the need of connecting parts with misaligned waveguides, e.g., with polarization axes having relative angles of 90 degrees, without excluding rotations of different magnitudes.
Up to now, for couplings of this kind it was necessary to prepare intermediate elements between the two guides generally known as "twists."
These twists, besides being additional elements and therefore introducing hindrance, costs, and never yielding a perfect setup even if prepared with sophisticated means and workings must always be made on a case by case basis and do not lend themselves to being prepared for universal uses.
Such twists are extensively used in the field of telecommunications but no wireless set manufacturer finds it convenient to produce them in their own plant. Outside manufacturing of twists is however extremely onerous and adversely affects the cost of equipment.